The shape of most modern ship hulls follows a long line of tradition, dating back hundreds if not thousands of years. As shipbuilding progressed from dugout canoes to triremes, to caravels, to ironclads, to modern hundred-thousand-ton cruise ships, many things changed. The size, modes of propulsion and construction materials have evolved, yet the same plow-shaped hull remains on the vast majority of today's displacement-type vessels. This is particularly true of the larger heavier boats plowing the oceans today, such as commercial transport ships, cruise ships and aircraft carriers.
While many glider-type hull designs have been developed in recent decades, few of them are practically adaptable to heavier ships. The ships that would most benefit from improvements in safety, comfort, stability, structural rigidity, maneuverability and fuel economy continue to rely on inefficient hulls of centuries-old design.
One major deficiency of the plow-bow-shaped hull is the lack of stability. Tremendous structures of modern vessels tower over the water, perched on thin narrow waterlines. Under the water, huge keels are often required to balance out and provide some lateral (side-to-side) stability to the ship. The keels often extend to great depth, preventing ships from operating in most of the world's ports, unless such ports are specifically adapted for modern ocean liners. Long keels greatly increase the risk of ships running aground, and the risk of underwater collisions with submarines and mines (in areas of past or present military conflicts). Ship keels are a great source of injury to large marine animals.
To effectively counter-balance the above-the-water structures of a vessel and prevent capsizing, the keels must be filled with ballast or otherwise made heavy. The keels are usually large in order to take advantage of water resistance in minimizing lateral roll. Large and heavy keels required for today's ships produce powerful frontal resistance and friction against water, reducing speed and increasing the power consumption. With record and rising fuel prices and the predicted reduction of global oil output in the next several decades, fuel-hungry vessels of today are a source of great concern to the shipping companies and to the expanding, interconnected global economy, where most products in intercontinental trade are shipped in heavy displacement-type merchant vessels. Increased costs of shipping, caused by inefficient shipping vessels, translate to increased costs of imports, reduced exports and overall strain for the global economy.
The keels help little with the bow-to-stern pitch. It is not unusual to observe the dramatic images of bows of medium and large navy cruisers dipping under the waves and flying up, splashing tons of water in choppy seas or at high speeds. Continued stress on the hull, resulting from the pitch also leads to reduced service life and increased maintenance costs of the vessels.
Lateral rolling and pitch on high seas was always accepted as an intrinsic part of seafaring. Even today, with cruise ships doubling in size every decade or so, many people suffer from sea sickness on cruise vacations. For this reason alone, tens of millions of people avoid cruise vacations. If cruise companies could offer their services on vessels that were practically free of roll and pitch, their incomes, and the popularity of this type of vacations would greatly increase.
Similarly, the roll and pitch on military ships, such as aircraft carriers, or cruise missle-launching ships may complicate takeoff and landing of aircraft, or launching of missiles in rough seas. On commercial transports, the roll and pitch may lead to the spoilage of produce. Movement causes products, such as fruits to move and rub against one another, leading to spoilage. One apple in a cargo of hundreds of boxes may become spoiled and release juices. Rocking motion of the ship will distribute the juices from the spoiled apple to other apples in the barrel, or other boxes, which too will become rotten. Similarly, with transport of any liquid medium, staking and movement of the medium will redistribute bacteria and oxygen throughout the container, thus accelerating deterioration and spoilage.
Of course, roll and pitch increases the risk of movement of cargo within the holds of the ship and the risk of ultimate capsizing of the ship. Uneven loading, overloading, sharp turns, can all lead to disasters on the ships with traditional plow-shaped hulls. Stories of overturned ferries, with hundreds of lives lost, are frequent in the news. Unlike the dugout canoes modern ships are not made out of floatable materials. So, not only capsizing, but any breach in the thin shell separating the interior of the ship from the ocean can cause a catastrophe. A collision, or a strike of a reef or an iceberg against the buttom of a ship is often sufficient to send thousands of people to a watery grave.
In the best case, the propellers extending from under the ship's bottom will take the brunt of the collision. But this will render the ship immobile. Propellers—the vital element of ship's mobility are open and vulnerable to damage from collision and/or entwinement with ropes, seaweed and other debris.
Therefore, there is a long-standing and unfulfilled need in the art for a new type of ship, with a new type of vessel hull. This new hull should provide improved speed and fuel efficiency. It should improve ship's stability, preventing capsizings of boats from overload and improper distribution of weight. It should reduce roll and pitch experienced by cargo and passengers on high seas. The new hull should protect the propellers from damage and entwinement with ropes and seaweed. It should provide a rigid frame for reducing the stress experienced by vessel's body. It should also protect the ship from punctures in the event of underwater collisions or ship running aground. The present invention achieves these objectives and provides numerous other benefits.